I saw your recent tweets and request for evidence and thought I would send you a quick note detailing my views.
In terms of evidence for the phonological approach, it undoubtedly is the proven way to support children to decode writing. However, as you have noted, being able to decode writing is not the same as being able to comprehend it. Being able to decode does have an impact on motivation and desire to understand what is being read, but that does not necessarily translate to being able to comprehend. I have worked with a number of children who are able to read aloud, but cannot tell you about what they have read. [It's very interesting you say this, because some phonics champions seem to think this is rare or insignificant. I've heard a good few teachers mention this. Ed. ] It seems likely that decoding correlates with comprehension but is not causal.
The problem is decoding and understanding are two different skills, the latter being a largely language based one. Children need to have been exposed to and heard words in context before they can understand them - it takes a skilled reader indeed to read a new word and work out its meaning through analysis of the context it is presented in. [I'm curious you say this, because in my experience, I've found that some very young children can indeed come across a new word, take a cue from, say, the initial letter, put that into the mix with awareness of context in the sentence and get the meaning from the sentence. Ed. ]
Vocabulary programs look to be useful for aiding comprehension, although research on the area is quite dated now. However, a vocabulary program is difficult to implement if a child is unable to decode the words. So I think the focus on phonological decoding is a relevant one - for the vast majority of children it helps them to read and comprehension is developed naturally through exposure to print and vocabulary.
I think the questions you raise are very relevant and interesting. My view is that phonics teaching has a place, but I am not sure that it requires the money spent on it. Tommy Mackay's work in Dunbartonshire used a considerably cheaper package than I see many schools investing in and saw fantastic results - although it should be noted it wasn't solely down to the phonics package. It is simply an amazing piece of work - he set out to, and was largely successful in doing so, eradicate illiteracy in a whole town. [ Should this be better known? You say 'considerably cheaper' - that's important. And you say 'wasn't solely down to the phonics package'- again, this is something that 'our side' has been trying to say all along, isn't it? ]
In my work, I rarely advocate a phonics-only approach and at the least try to get children to have access to paired reading (which done properly includes questioning of materials which aids comprehension) and vocabulary input as well. Too often it seems that the onus is placed on schools to teach children to read, when actually positive literacy outcomes tend to be related to factors outside of them. And skilled readers enjoy reading! Where's the fun?!
What we often forget is that this process of learning to read is a neurological miracle. Reading, in evolutionary terms, is a very recent development that has, generally, been relativelyeasily learned by the vast majority of humans. The central argument is that reading and writing must utilise neurological processes that have evolved over millennia - and these, appear, to be the ones linked to our understanding and use of language and visual processing. [ the key word here is 'linked' , is it not? Isn't the problem with 'first, fast and only' that the phonics gets detached (ie not linked with ) from the rest of the processes needed to make up 'reading for meaning' ? ]
Some of the key references I've used in my work are:
Brooks, G. (2007) What works for pupils with literacy difficulties?: The effectiveness of interventions schemes.
Dehaene, S. Reading in the brain: Neuronal mechanisms of a cultural invention.
Elliott, J. G. and Gibbs, S. (2008) Does Dyslexia Exist? Journal of Philosophy of Education.
Nation, K. and Angell, P. (2006) Learning to read and learning to comprehend, London Review of Education.
Snowling, M. J. and Hulme, C. (2011) Evidence-based interventions for reading and language difficulties: Creating a virtuous circle, British Journal of Educational Psychology.
Solity, J. and Vousden, J. (2009) Real books vs reading schemes: a new perspective from instructional psychology, Educational Psychology.
Paired reading resources: http://www.dundee.ac.uk/eswce/research/projects/trwresources/reading/
These are a tiny selection from a wide range of research done in this area, but are the ones that I have found most useful in supporting schools and families to address reading difficulties.